Human brain may stay active for hours after death, reveal researchers

What happens to the body after death? We've all heard the stories about how some animals – namely snakes – can still bite after they've been decapitated because their brains require less oxygen and thus stay active longer, but what about humans?

According to a new study, it may actually take hours for our brains to fully shut down after our hearts stop pumping, which means we are technically dead but may be somewhat aware of what is happening around us

One question that has baffled mankind is “after-death experience” or the experience after the heart stops beating. There have been anecdotal reports of a person being able to understand and hear what is happening around them even after they have been declared dead.

A team of researchers have found that the brain works for a while after the heart has stopped. The research is reported in an a journal paper titled, ‘AWARE—Awareness during Resuscitation—A prospective study.’

Study leader Dr Sam Parnia said that the patients could describe in details what happened around them. He explained that the time death is declared is the one when the heart stops beating. As the heart stops beating, it stops pumping blood to the brain and slowly the brain begins to shut down, he explains. He added that this process of the brain shutting down slowly may take hours and the person may be dead during this time but aware of their surroundings.

The team hopes that this study would help in the management of cardiac arrests and also prevent brain damage during resuscitation of such patients. Dr Parnia said, “At the same time, we also study the human mind and consciousness in the context of death, to understand whether consciousness becomes annihilated or whether it continues after you’ve died for some period of time – and how that relates to what’s happening inside the brain in real time.”

What this study means is that people are trapped inside their dead bodies for a while after they are declared dead. According to Dr Parnia, people change after they have had an ‘after-death’ experience.

Dr Parnia warned that unlike the Hollywood movie ‘Flatliners’ people who return from this experience do not come with extra visions or memories.

The science fiction movie showed a group of medical students who simulated a near death experience experiments to find themselves with visions and memories from the past.

He explained that the thinking region of the brain or the cerebral cortex slows down and flat lines but the brain cells are still active.

When CPR is given the heart is started again and so does the brain function. He said, “If you manage to restart the heart, which is what CPR attempts to do, you’ll gradually start to get the brain functioning again. The longer you’re doing CPR, those brain cell death pathways are still happening — they’re just happening at a slightly slower rate.

Dr Parnia added, “What tends to happen is that people who’ve had these very profound experiences may come back positively transformed. They become more altruistic, more engaged with helping others. They find a new meaning to life having had an encounter with death. But there isn’t like a sudden magical enhancement of their memories. That’s just Hollywood jazz.”